Portable tool analyzer



Nov. 10, 1959 A. FRAZIER ETAL ZORTABLE TOOL ANALYZER Filed Dec. 26, 1956RIVE) INVENTOR. GEORGE A. FRAZ/El? 8 RILEY A. SEXTON BY PORTABLE TOOLANALYZER George A. Frazier, Fort Worth, and Riley A. Sexton,

Arlington, Tex., assign'ors to General Dynamics Corporation, San Diego,Calif., a corporation of Delaware Application December 26, 1956, SerialNo. 630,525

3 Claims. (Cl. 73-116) This invention relates to portable tool analyzersand more particularly to a portable pneumatic hand tool analyzer whichmay be moved to where the tools are in use for testing.

Heretofore when a pneumatic hand tool did not seem to function properlythe operator returned the tool for servicing. The only standards set bythe manufacturer on the performance of his tool were revolutions perminute and air consumption of the tool. If the tool did not meet thesestandards the repairman examined it, took it apart, and replaced partsthat appeared to be worn or damaged. When it was put back together againthe repairman had no way of determining whether its performance would besatisfactory under normal load conditions. The tool may pass therevolutions per minute and air consumption test and still not havesatisfactory performance or be adequately serviced. A tool that checksup to standard in the tool service area still may not give satisfactoryperformance on the job. Sometimes the tool trouble may be traced to lowair pressure due to defective air valves, Worn fittings, undersize hoseor other obstructions in the air line. Without pro-per testing equipmentand performance standards there could be no preventive maintenanceprocedures. Costly repairs have resulted through failure to detectneglect or trouble in advance. Lack of proper bearing lubrication,binding spindles or other factors producing undue friction reduce thenormally long life of the precision tools, which otherwise might havebeen avoided with proper testing and maintenance procedures.

These and other problems are now overcome by this invention whichconsists of a mobile test cart equipped with testing devices forchecking the performance of rotary-type hand tools, air lines andfittings. It has been determined that for a true test of a toolsperformance it is necessary to know the air consumption of the tool, theair pressure in the air line, the revolutions per minute of the toolwithout load, and the horsepower under load. Suitable instruments fordetermining these factors are provided as well as an oil spray devicefor lubricating the tool being checked.

It is therefore an object of this invention to provide for a mobile toolanalyzer.

Another object is the provision of a mobile tool analyzer which may beused to check the tool at its use location.

Another object is the provision of a pneumatic tool analyzer which alsochecks the air supply to the tool.

Another object is the provision of a pneumatic tool analyzer whichcontrols the air supply while obtaining performance data.

Still another object is the provision of a pneumatic tool analyzer whichwill test a tools performance.

Still another object is the provision of a pneumatic tool analyzer whichchecks the available air pressure, the air consumption of the tool, therpm. of the tool without load, and the horsepower of the tool underload.

Other objects and features of the present invention will be readilyapparent to those skilled in the art from the following specificationand appended drawings wherein is illustrated a preferred form of theinvention, and in which:

Figure l is a front View of the analyzer; and

Figure 2 is a rear view with the rear doors removed.

Referring now to Figure 1 there is shown the analyzer cart 11 mountedfor movement on rollers 12 and swivel casters 13. On the top of thecabinet are two Prony brakes 16 and .17, one for measuring inch poundsof torque and the other for measuring foot pounds. Suitable linkage andweights are mounted within the cabinet for actuating the torqueindicators 18 and 19 mounted on instrument panel 21 at the rear of thetop of the cabinet. An air flow meter 22, line air pressure gauge 23,tachometer 24 and volume tank pressure gauge 26 are also mounted on theinstrument panel 21. Separate switches 25 and 25A permit independentreading from the tachometer 24 of spindle speed of either of the brakes16 and 17.

Referring now to Figure 2, wherein is shown the rear view with the doorsremoved, the air hose 27 from a remote air supply (not shown) isconnected to an air filter 28 which removes any foreign matter from airpassing through the line. The air pressure is then regulated byregulator 29 to the desired pressure as shown by the regulated airpressure gauge 23. The air consumption is then measured directly by airflow meter 22 in cubic feet per minute. From the air flow meter the airpasses into a volume tank 31 which maintains the air at a constant airpressure. Connected to the volume tank is a lubricator 30 for spraying afine mist of oil through each tool being checked. Air hose 32 is forconnection of an air tool to the controlled air supply. The rotary shaftof the air tool (not shown) is operably connected to drive spindle 33 onProny brake 17. The spindle turns the tachometer generator 35 which isconnected by switch 25 to the tachometer 24. If a smaller tool is beingchecked Prony brake 16 is used, and switch 25A connects tachometergenerator 35A to the tachometer for reading.

Although other types of instruments and components may be used, thefollowing were found to be satisfactory in the preferred embodiment:Airline filter #65B and Airline Lubricator #65F from Keller ToolCompany, C. A. Norgren type 242 regulator, Airflow meter Tool 0 MeterNo. TO-40 from New Jersey Meter Company, Westinghouse Tachometer typeNC-37, a 0100 p.s.i. volume tank pressure gauge and Chantillon 30 torquein- 'dicators.

When the rotary type hand tool to be checked has been set in the Pronybrake 16 or 17, and connected to the air supply through the flexiblehose 32, the tool is ready for testing. Since most tools are designedfor operation at p.s.i., the air pressure is set to that amount. Sincethe manufacturer specifies an r.p.1n. for each tool, the pressure isreleased from the Prony brake to get the tool started and a free speedreading. The r.p.m. without load is now checked. A load is now appliedby rotating knob 34, tightening arms 36 against wheel 37. This torque isread from torque indicator 18 or 19 to get the horsepower under load.Three simultaneous readings are obtained, the rpm. from the tachometer24, the torque from the spring scale reading, and air consumption fromthe air flow meter. The air pressure gauge 26 is checked to insure theproper pressure regulation. The horsepower may be computed from ther.p.m. and torque or read from a chart having these relationships. Itshould be noted that a fin spray of oil mist from lubricator 3tlubricates the tool while the test is being performed. Performance ofelectrical rotary type hand tools may also be tested with the analyzer.The r.p.m. without load, and horsepower under load may be checked in thesame manner as pneumatic tools.

Because manufacturers do not furnish data on tool performance other thanair consumption and r.p.m., new

standards of performance must be made for each of the large number ofhand tools by types and brands. This may be done by testing each newtool before it has been used and recording the information on a cardforready reference. When a sufficient number of tools of a particulartype (twenty is considered an adequate number) have been tested, astandard of performance, with upper and lower limits, may be devised forthat too]. Thus, by comparing data from the tool under test with theestablished standard of performance, the serviceability of the tool maybe checked. The results may be recorded on individual tool maintenancecards for use by the repairman in overhauling the tool. Moreover, thestandards established from testing new tools and the performance oftools in use serve as a guide to purchasing new tools.

No longer need the claims or reputation of the manufacturer be reliedupon since actual tool performance data is now available. By testing andlubricating regularly minor faults may be detected and remedied beforethey become serious. Since expensive gears and bearings are oftenaffected by even one damaged or worn part, being able to detect neglectand future trouble in advance can save costly repairs. Historical dataof repair costs and performance taken from individual tool maintenancerecords may be used to provide justification of new tool purchases.Frequently tools have been overhauled when it would have been morepractical and inexpensive to replace the tool.

Many benefits are to be realized from the use of the tool analyzercomprising this invention. Among them are:

(1) Increased production resulting from increase in the efficiency ofthe tools,

(2) Lost time reduction because of better tool service and fewer in usebreakdowns,

(3) Extended life of tools due to preventative maintenance measures, and

(4) Reduced cost in tool repairs.

While certain preferred embodiments of the invention have beenspecifically disclosed, it is understood that the invention is notlimited thereto as many variations will be readily apparent to thoseskilled in the art and the invention is to be given its broadestpossible interpretation within the terms of the following claims:

What we claim is:

1. A mobile tool analyzer for checking pneumatic rotary tools at theirplace of use comprising a movable test cart, an instrument panel on saidcart, an air conduction path including an air filter mounted on saidpanel and adapted for connection to a remote source of air pressure,valve means for controlling the air supply from said source, meansconnected to said path for measuring the rate of air passagetherethrough, a volume air supply tank for maintaining air pressure at aconstant predetermined value, means for injecting an oil spray mist intosaid path, flexible hose means for connecting a pneumatic tool to saidspray means, counting means for indicating the r.p.m. of said toolcomprising a rotatable spindle adapted to be operably connected to saidtool and rotated thereby, an electrical generator means connected to anddriven by said spindle for generating an electrical output indicative ofthe speed of rotation of said spindle, and readout means mounted on saidpanel and connected to said generator means for indicating the r.p.m. ofsaid spindle corresponding to the electrical output of said generatingmeans, friction means for applying a load to said tool comprising awheel rotatably mounted to turn with said spindle, means frictionallyengaging said wheel for retarding the rotation of said spindle andproducing a torque thereon, and indicia means on said panel andoperatively connected to said friction means for indicating the torqueon said spindle.

2. A mobile tool analyzer for checking pneumatic rotary tools at theirplace of use comprising a movable test cart, an instrument panel on saidcart, an air conduction path including an air filter mounted on saidpanel and adapted for connection to a remote source of air pressure,valve means for controlling the air supply from said source, meansconnected to said path for measuring the rate of air passagetherethrough, a volume air supply tank for maintaining air pressure at aconstant predetermined value, flexible hose means for connecting apneumatic tool to said air path, counting means for indicating ther.p.m. of said tool comprising a rotatable spindle mounted on said cart,adapted to be operably connected to said tool and rotated thereby, anelectrical generator means connected to and driven by said spindle forgenerating an electrical output indicative of the speed of rotation ofsaid spindle, and readout means mounted on said panel and connected tosaid generator means for indicating the r.p.m. of said spindlecorresponding to the electrical output of said generating means,friction means for applying a load to said tool comprising a wheelrotatably mounted to turn with said spindle, means frictionally engagingsaid wheel for retarding the rotation of said spindle and producing atorque thereon, and indicia means on said panel and operativelyconnected to said friction means for indicating the torque on saidspindle.

3. A mobile tool analyzer for checking pneumatic rotary tools at theirplace of use comprising a movable test cart, an instrument panel on saidcart, an air conduction path including an air filter mounted on saidpanel and adapted for connection to a remote source of air pressure,valve means for controlling the air supply from said source, meansconnected to said path for measuring the rate of air passagetherethrough, a volume air supply tank for maintaining air pressure at aconstant predetermined value, fiexible hose means for connecting apneumatic tool to said air path, a pair of rotatable spindles eachadapted to be operably connected to said tool and rotated thereby, apair of electrical generator means each connected to and driven by oneof said spindles for generating an electrical output indicative of thespeed of retation of each of said spindles, and a single readout meansmounted on said panel and alternately connected to each of saidgenerator means for indicating the r.p.m. of its associated spindlecorresponding to the electrical output of said generating meansassociated therewith, friction means for applying a load to said toolcomprising a pair of wheels each rotatably mounted to turn with one ofsaid spindles, means frietionally engaging said spindles and producing atorque thereon, and indicia means on said panel and operativelyconnected to said friction means for indicating the torque on saidspindles.

References Cited in the file of this patent UNITED STATES PATENTS2,004,950 Jenkins June 18, 1935 2,310,974 Lumm Feb. 16, 1943 2,366,889Westberg et a1. Jan. 9, 1945

